Combination firearm and grenade



Nov. 20, 1962 J. VILBAJO 3,064,381

COMBINATION FIREARM AND GRENADE Filed Feb. 25, 1960 FIG.5

INVENTOR JEAN VILBAJO yan ATTORNEY) E tates fine 3,064,331 (ZOMBINATIUN FIREARM AND GRENADE Jean Vilbajo, Burcht, Belgium, assignor to A.V.R., Achat, Ventes, Representations, Societe Anonyme, Brussels, Belgium Filed Feb. 23, E60, Ser. No. 19,443 Claims priority, application Belgium Get. 28, 1959 4- Claims. (Cl. 42l) In a general way, grenades and similar projectiles intended to be shot from a firearm, which most of the time is a rifle, the barrel of which is fitted with a grenade sleeve, are made of a head comprising a cylindrical middle part and two conical ends; the forward butt end is thereby fitted With an impact device, whereas the rear butt end extendsinto a tubular tail which carries the fins.

Such projectiles are slipped over the muzzle end of the barrel and are propelled by a normal cartridge fired from aforesaid firearm.

It follows from this set of conditions, that the ballistic characteristics attending the firing of such projectiles are essentially dependent on the comportment of the gaseous medium inside the barrel, which comportment is well known to be essentially variable from one firearm to the next. It is also well known, that in such shooting, account must be taken as well of the pressure in the gaseous medium which expands in the course of combustion, as of the elfects of the shock waves, which are essentially variable both with respect to their amplitude and their intensity.

It follows therefrom that, on the one hand the ballistic conditions are diflicult to'control, and on the other hand that the firearm itself can be subjected to local stresses which are extremely variable, and cansometimes even prove to be dangerous.

The object of the present invention is to bring about improvements to aforesaid projectiles in order to eliminate systematically all these disadvantages by making, so to say, the ballistic behaviour of such projectiles independent of the actual ballistic conditions appertaining to the firing of cartridges by the firearm. These improvements essentially consist in providing the projectile itself with the charge needed for its propulsion, the part played by the firearm being limited to the ignition of this propelling charge.

Another characteristic of the present invention is the means applied for-rendering aforesaid projectiles practically autopropelled. This means may be such that it requires no modification whatever of the normal manufacturing of aforesaid projectiles, as the ignition means in question can be fitted subsequently and easily put into its correct position. This position is such that, when the projectile is normally fitted on the muzzle, aforesaid ignition device fastened to the projectile fits onto the end of the muzzle and preferably even penetrates slightly ,into the barrel in such way that aforesaid firing device meets on aforesaid muzzle a highly resistant support against the reaction stresses at the moment of firing.

Still another characteristic of the present invention is to be found in the simple way in which such propelling device can be made, whilst being extremely efiicient.

In this particular form of embodiment, the propelling device mainly consists of a hollow cylindrical body which can be adjusted by a sliding fit into the bottom of the tubular tail of the projectile, this hollow body containing, on the one hand the propelling charge, and on the other hand an ignition relay, both parts being separated from each other by at least one passage comprising a device which closes automatically at the very instant when aforesaid propelling charge is ignited.

These various characteristics, as well as numerous further constructional details which add considerably to the originality of the object of the present application, will appear more clearly from the following detailed description of a preferred form of embodiment which however is given merely by way of example without implying any limitating factors, as the means for securing the autopropulsion of such projectiles can as such be designed in any other way than that which is indicated, without exceeding the scope of the present invention.

The following description is given with reference to the appended drawings in which:

FIGURE 1 represents in a most summary and diagrammatic way, a plan view, with partial section, of the application of the device conforming to the present invention, to a grenade fitted With fins;

FIGURE 2 represents half a front view and half a radial section of one very characteristic propulsion device;

FIGURE 3 is an exploded view of the component parts of the device;

FIGURE 4 is a diagrammatic radial section of the device represented in FIGURE 2, at the moment when the propelling charge is being ignited;

7 FIGURE 5 is an end view in the direction of arrow F of FIGURE 3.

In the diagrammatic representation of FIGURE 1, a

.rnostsummary sketch is given of a projectile consisting of the head l, the tubular tail 2 and the fins 3.

According to the present invention, the propelling device 4 is introduced and held in the bottom of the tubular tail 2. This device carries the charge which is going to propel the projectile, as well as the means for igniting this charge with the help of the firearm onto the barrel of which the tubular tail 2 of aforesaid projectile Will have been slid. After the firearm is discharged, the propelling device 4 will separate from the projectile.

FIGURES 2 to 5 represent one particular form of embodiment of aforesaid propelling device 4. In the present instance, this device consists of a hollow cylindrical body 5 the outside diameter D of which is practically equal to the inner diameter D of the tubular tail 2 of the projectile so that aforesaid hollow body 5 might be adjusted with a comparatively easy fit. This hollow body 5 extends into a hollow part 6 with inside screw thread, cornmunicating with aforesaid hollow body 5 through a central opening 7; at the bottom of this hollow part 6 a disc 8 is applied, which disc is provided with holes 9 symmetrically disposed around its center. In the hollow part 6 the cylindrical threaded part 10 of a second tubular part 11 is screwed. This tubular part 11 terminates in a conical end 12. The component made up of aforesaid threaded part 10 and aforesaid part 11 has an axial bore which comprises in succession, starting from the conical end 12, a first bore 13, a second bore 14 of smaller diameter, a conical passage 15 which converges towards the center of aforesaid threaded part 10, and another conical passage 16 which is an extension of the former but diverges toward the rear face of aforesaid conical part 10. The conical passage which was mentioned last is such that it covers the whole of the various openings 9 in the inset disc 8. In this second conical diverging passage 16 a ball 17 is placed, the diameter of which is slightly larger than the smallest common diameter of both aforesaid conical passages 15 and 16.

The propelling charge 18 is contained in the hollow body 5 and held in its place by a cup 19 which can be covered by a lid Ztl fitted for instance in an inner groove 21 and held in its place by a peripheral setting 22. On the other hand, a relay 23 is fastened in the second bore 14 by means of a ring 24 onto which is applied a thin disc 25 of some very easily tearable material such as paper. Both tubular parts 6 and 11 are each provided with two diametrically opposite flats 2627 and 2829 respectively, intended for accommodating appropriate Wrenches.

As shown in a very diagrammatic way in Figure 1, the propelling device may thus in this way be introduced into the tubular tail 2 and fastened at the bottom of the latter against the adjacent part of head 1, either by a simple tight fit, or by means of some appropriate adhesive of any known kind.

As is also diagrammatically represented in FIGURE 1, the projectile which has thus been improved can be fitted in the normal way over the muzzle 30', which latter can be provided with a grenade sleeve 31 or any other well known device. All that needs be done then, is to make use of some means which will propagate through the barrel of the firearm a flame or a wave capable of igniting the relay 23 which, in turn, ignites the propelling charge 18. The propelling device conforming to the present invention fulfills a double function of which the first consists inimparting to the projectile a sufiicient amount of energy in order that it might reach its target, whereas the second consists in preventing the operation of the auto matic cocking mechanism of the firearm. It is. for this reason that the automatic closing device of the central passage in the propelling device, which is the object of the present invention, has been provided. What happens in fact is that the ball 17, on account of the back-firing eflect of the gaseous medium, is firmly applied against the junction of the two conical passages 1516, thus ensuring an absolutely hermetical sealing of this passage, and hence preventing the expanding gases from moving towards the cocking mechanism of the firearm. This is extremely important, as it systematically eliminates all danger of an unwanted cocking of the firearm. It follows therefrom that the latter, even if it carries a magazine loaded with ordinary cartridges, can be instantly used without any preliminary precautions, for firing projectiles of the type which has been described above, so that it is possible to alternate the firing of such projectiles with that of normal rounds, and vice-versa, which endows the firearms and those which are called upon to use them with a considerable versatility and an accelerated firing power. Moreover, this new means for propelling such special projectiles practically excludes any mishaps and confers the highest degree of safety.

It is apparent that in accordance with the present invention the primer of the propellant charge is constituted by the relay 23 which is directly ignited by the gases produced by the firing of the firearm. The ball 17 provides a closing means which is open at the moment of the firing, so that gases produced by the firing action are able to reach and ignite the relay. On the other hand, the passage is closed at the moment the propellant charge is ignited so that the gases produced by the propellant charge are not able to enter the barrel.

The various components of this propelling device can of course be modified or adapted in various Ways, either by changing the shape, the dimensions and the relative position of the charge, or by making use of another means for prevening the gases from back-firing towards the cocking mechanism, or further by introducing different means for systematically blocking their way to the rear.

It will be noticed indeed, that in the device as described above, the ball 17 is compelled to travel along the conical wall of passage 16, considering that the openings 9 of disc 8 are to this effect disposed around the center of the latter. It is obvious that any other device leading to the same result could be used.

The present invention concerns not only the application as such, to any projectile of the type which has been described, of an individual means of propulsion consisting substantially of a charge and of a device which prevents the back-firing of the gases towards the cocking mechanism of the firearm, but also the device as such, the projectile fitted with this device, as well as the particular device such as it has been described above and represented in the appended drawings.

What I claim is:

1. In combination a firearm having a muzzle, a projectile fitted upon said muzzle, a cartridge fitting into said projectile and comprising a cylindrical casing having a front explosive-receiving chamber, a rear end and an axial passage having a frusto-conical portion communicating with said chamber and converging in the direction toward said rear end and another frusto-conical portion constituting a continuation of the first-mentioned frusto-coni; cal portion and diverging in the direction toward said rear end, an ignition relay in the second-mentioned frusto-conical portion adjacent said rear end, and a ball located in the first-mentioned frusto-conical portion and movable to close the passage between the two frusto-conical portions upon ignition of the explosive in said chamber to prevent expansion of gases produced by said ignition into the muzzle of said firearm.

2. In combination a firearm having a muzzle, a projectile fitted upon said muzzle, a cartridge fitting into said projectile and comprising a casing having a cylindrical portion containing an explosive-receiving chamber, and a cylindrical passage communicating with said chamber, a tubular portion firmly connected with said cylindrical portion and another tubular portion threaded at one end into the first-mentioned tubular portion, the second-mentioned tubular portion having a frusto-conical portion communicating with said cylindrical passage and converging in a direction away from the threaded end and another frusto-conical portion constituting a continuation of the first-mentioned frusto-conical portion and diverging in a direction away therefrom, an ignition relay carried in the second-mentioned frusto-conical portion, a ball located in the first-mentioned frusto-conical portion and movable to close the passage between the two frusto-conical portions upon ignition of the explosive in said chamber to prevent expansion of gases produced by said ignition into the muzzle of said firearm, and a perforated disc located between said cylindrical passage and the first-mentioned frusto-conical portion.

3. A combination in accordance with claim 2, wherein said perforated disc has a plurality of holes disposed symmetrically about the center of the disc.

4. A combination in accordance with claim 3, wherein the holes of said disc are inscribed in a circle the radius of which is at most equal to the largest diameter of the first-mentioned frusto-conical portion.

References Cited in the file of this patent UNITED STATES PATENTS 

